Chemical, rheological, and sensorial properties of Baladi bread supplemented with buckwheat flour produced in Egypt

This research aimed to enhance the nutritional and sensory qualities of Balady bread by adding locally Egyptian buckwheat flours, Fagopyrum esculentum (FE) and Fagopyrum tataricum (FT), to Hard Wheat Flour (HWF) 82% extraction at three levels (10%, 20%, and 30%). The chemical composition, rheological properties, color, sensory evaluation and stalling of the balady bread were determined. The chemical composition of raw materials revealed that FE was significantly (P ≤ 0.05) higher in protein and fat contents compared to HWF and FT. While FT was higher in fiber and ash contents. The findings show that a 30% replacement with FE or FT significantly enhances the bread's nutritional profile, notably increasing protein, fiber, ash, and moisture content. Rheological analysis revealed that FE and FT alter dough handling, with a notable improvement in dough stability and mixing tolerance at 30% FT. Sensory evaluation indicated acceptable qualities even at higher substitution levels, although 30% FE showed slight declines in certain attributes. Furthermore, bread supplemented with 30% FT demonstrated slower staling and potentially extended shelf life. These results highlight the potential of FE and FT as nutritional enhancers in bread formulations, with 30% FT emerging as the optimal replacement level for balancing nutritional benefits and sensory acceptance.

respectively.Recombinant lipoxygenase was found to improve both farinograph and extensograph measures 11 , while mealworm powder was observed to reduce dough elasticity 12 .The effects of barley and maize flour on extensibility were also investigated, showing varied impacts 13,14 .However, Pasting properties of Hard wheat flour in Baladi bread can be influenced by ingredient addition and substitution.Abdel-Kader 15 found that enriching Baladi bread with decorticated cracked broad beans flour increased water absorption, arrival time, and dough development time.The addition of soy flour impacted the sensory and rheological properties of wheat bread 9 .Choi et al. 16 discovered that substituting normal and waxy-type whole wheat flour decreased pasting viscosity.While, the chemical composition of Baladi bread has been diversified to explore the influence of various ingredients.Hadidy and Rizk 17 focused on enriching fatty acids with coriander seeds.The elemental composition and sensory attributes of bread supplemented with barley and corn flours were evaluated by Hussein et al. 18 .Mohamed et al. 19 enhanced bread with folic acid and whole grains, improving nutritional content.The enrichment of red algae was studied by Yousef et al. 20 , while Hussein et al. 21assessed low-protein variants.Ingredients like seed coats, rice bran, and watermelon rinds were experimented with to assess changes in chemical and sensory properties, as well as potential health benefits [22][23][24][25] .Also, the color attributes of Baladi bread can be altered by ingredients and processing techniques.Barley and corn flour supplementation changed bread color 18 , while guar gum breads mimicked French bread color 26 .Whey protein was noted to darken the crust of breads 27 .The influence of coriander seeds, nano-powders, and red algae on color parameters was highlighted 17,20,28 .The impact of watermelon rinds and rice bran was assessed 23,25 , and wheat grain fertilization techniques were compared 29 .However, olive oil amounts did not significantly change ciabatta bread color 30 .Lastly, Various additives' impact on Baladi bread's sensory properties and freshness during storage has been extensively studied.The addition of grape seed, quinoa, and breadfruit flours showed improvements in nutritional and sensory aspects [31][32][33] .Barley and red algae were observed for nutritional gains but with some sensory changes 18,20 .Watermelon rind flour could replace up to 15% of wheat flour without affecting sensory attributes 25 .The role of enzymes and storage temperature on bread freshness was emphasized by Ghoshal et al. 34 and El-Sayed 35 while higher protein content and dairy by-products were linked to extended freshness and shelf-life 29,36 .

Buckwheat varieties
In a study from 2018 to 2020, Fagopyrum tataricum and Fagopyrum esculentum were grown in Bilbies city, Sharkia and Sadat City, Monofiya in Egypt to examine their growth, productivity, and quality under different timings.Grains were harvested, mixed, dried, and purified.The buckwheat seeds, bought from a commercial company based in California USA, were airfreighted to Egypt, inspected internationally and nationally, passed quarantine checks, and underwent germination tests before planting in the study areas 34,37,38 .
The Authors obtained the necessary approvals from the Ministry of Agriculture and Land Reclamation (MALR) on importation and cultivation (in both mentioned locations) of Buckwheat seeds for the abovementioned cultivars.However, imported varieties also have got phytosanitary certificate issued by USDA and all the seeds delivered directly from the producer through airfreight, as a comply with relevant institutional, national, and international guidelines and legislation.

Wheat flour and other ingredients
Hard Wheat flour (HWF) with an 82% extraction rate was sourced from the South Cairo Mill Company located in Giza, Egypt.Sugar, salt (sodium chloride), and yeast (Saccharomyces cerevisiae) were procured from the local market in Giza, Egypt, for use in the study.

Chemicals and solvents
In this research study, all the chemicals and solvents employed were of analytical reagent grade.Specifically, the solvents used, including trichloroacetic acid (TCA), thio barbituric acid (TBA), and DPPH (2,2-Diphenyl-1-picryl-hydrazyl), were procured from the Gomhoria Company for Chemical and Trading, based in Cairo, Egypt.

Technological treatment
Preparation of flour mixtures Buckwheat seeds were cleaned and moistened to 15% moisture content.Then, they were ground using a Quadrumat Junior flour mill and sifted through a 40-mesh sieve.The resulting flour was packed into plastic sachets.We mixed this buckwheat flour with hard wheat flour (HWF) with different proportions: 100% HWF, 90% HWF and 10% BWF, 80% HWF and 20% BWF, and 70% HWF and 30% BWF.

Rheological properties of dough
We assessed the doughs' rheological characteristics using farinograph, extensograph, and Rapid-viscoanalyzer (RVA) tests following the AACC 39 guidelines.

Preparation of Baladi bread
Flour blends (Table 1) were combined with yeast, salt, and water and mixed for 6 min.The dough fermented for 1 h at 30 °C and 85% humidity.Afterward, 125 g pieces were rested on a bran-sprinkled board for 45 min.Each piece was then flattened to 20 cm in diameter, proofed for 15 min between 30 and 35 °C, and baked at 400-500 °C for 1-2 min.Baked loaves cooled for 1 h before evaluation.

Sensory evaluation
Trained panelists, a group of 15 individuals, conducted sensory evaluations of the Baladi bread loaves following the methodology outlined by Hussein et al. 18 .Each sample was assessed based on the following criteria: 1. General appearance (worth 20 points) 2. Layers separation (worth 20 points) 3. Roundness (worth 15 points) 4. Crumb distribution (worth 15 points) 5. Crust color (worth 10 points) 6. Taste (worth 10 points) 7. Odor (worth 10 points) Panelists assigned scores to each of these attributes to evaluate the sensory characteristics of the Baladi bread loaves.

Freshness of bread
The freshness of Baladi bread loaves was assessed after packaging them in polyethylene bags and storing them at room temperature for 1, 3, and 5 days.The assessment was conducted using the Alkaline Water Retention Capacity test (AWRC), following the procedure initially developed by Yamazaki 40 and subsequently modified by Kitterman and Rubenthaler 41 .

Formula of Baladi bread
The formula for making Baladi Bread with different proportions of Buckwheat flour (Fagopyrum esculentum and Fagopyrum tataricum) along with the control sample.The ingredients used in the formula are as follows: • Hard wheat flour (HWF): 100% in the control sample, and varying percentages (90%, 80%, and 70%) in the samples with buckwheat.• Buckwheat flour (Fagopyrum esculentum and Fagopyrum tataricum): 0% in the control sample, and 10%, 20%, and 30% in the samples with buckwheat.• Dry yeast: 1.5 g in all samples.
• Salt: 1.0 g in all samples.
In summary, the formula details the proportions of these ingredients used to prepare Baladi Bread with varying levels of buckwheat flour, allowing for different formulations and experimental samples to be created.

Chemical composition
Moisture, protein, fat, ash, and crude fiber contents were assessed using the methods specified in the AOAC 42 (Association of Official Analytical Chemists) 2005 guidelines.To determine the carbohydrate content, the following formula was applied: Carbohydrates (%) = 100-(% protein + % fat + % ash + % crude fiber).This calculation method subtracts the percentages of protein, fat, ash, and crude fiber from 100% to estimate the carbohydrate content in the samples.

Statistical analysis
The collected results were statistically analyzed using an analysis of variance (ANOVA) method, as described in McClave and Benson's 43 reporting.

Rheological parameters
Farinograph parameters Table 2 and Fig. 1 assessed the Farinograph parameters of HWF supplemented with FE.HWF's 100% control displayed specific values for water absorption, arrival time, and dough stability.Notably, 10% FT reduced water absorption and dough stability, increasing the mixing tolerance index significantly.At 30%, a more balanced dough behavior emerged.Conversely, FT supplementation led to decreased dough stability but higher mixing tolerance, particularly at 20%.These results reveal that alternative flour type and level can significantly impact Farinograph parameters, influencing dough handling and product quality 44 .The interplay between dough stability and mixing tolerance underscores the nuanced effects of supplementation on rheological properties, consistent with prior research 8 .Flour supplementation's profound impact necessitates precise understanding and balance for optimal bread formulations.
Our results indicate that the type and level of supplementation have a significant impact on dough's mechanical properties and ultimately on bread quality.Understanding these extensograph parameters in the context of alternative flour types is crucial for optimized bread formulations.

Pasting profile (RVA)
Our study examined how Fagopyrum esculentum and Fagopyrum tataricum supplementation affect the pasting properties of Hard Wheat Flour (HWF)-based baladi bread as Table 4 and Fig. 3.The control sample showed a peak viscosity of 1192 CP, which declined with Fagopyrum esculentum and rose significantly with Fagopyrum tataricum, peaking at 4949 CP at 30% supplementation.These findings echo earlier research on the influence of various ingredients like soy flour and decorticated cracked broadbeans on pasting properties 9,15 .Moreover, Choi et al. 16 reported similar effects with whole wheat flour substitution.Pasting and peak temperatures also varied but stayed within narrow ranges.These alterations in pasting properties are crucial, as they provide insights into potential textural and sensory changes in the final bread product, affirming the significant role of ingredient supplementation in bread formulation.

Chemical composition of Baladi bread
Table 5 shows that the chemical composition of Baladi bread supplemented with FE and FT showed significant enhancements in key nutritional metrics.Specifically, the bread with 30% FE or FT supplementation had notably higher levels of protein, moisture, ash, and fiber compared to the control made from 100% HWF in agreement with Hadidy and Rizk 17 and Mohamed et al. 19 that observed improvements in fatty acids and micronutrients like folic acid when using different additives.However, Hussein et al. 18 extended this by examining mineral content, corroborating the increase in ash content seen in our study with FE and FT supplements.Also, Studies by Yousef et al. 20 and Sandak et al. 22 showed that unconventional additives like red algae and seed coats can also alter the bread's chemical composition.   nd Mezaize et al. 26 , which reported color changes in bread due to different ingredients.Similar to Aider et al. 27 and Hadidy and Rizk 17 , additions like whey protein and coriander seeds altered the bread's color.thus, incorporating FE and FT into Baladi bread significantly influences its visual attributes, potentially affecting its sensory appeal and marketability in agreeing with Elkatry et al. 31 , Milovanović et al. 32 , and Bakare et al. 33 .

Sensory properties of Baladi bread
The sensory properties of Baladi bread supplemented with Fagopyrum esculentum (FE) and Fagopyrum tataricum (FT) were assessed in Table 7, which is particularly significant.It provides a comprehensive view of how different levels of these supplements affect bread characteristics like appearance, layer separation, roundness, crumb distribution, crust color, taste, and odor.The results indicate that up to 20% FE or FT supplementation maintains comparable sensory qualities to the control (100% HWF), while a 30% supplementation leads to some decline in attributes like general appearance and crumb distribution.However, these findings are in line with Elkatry et al. 31 and Milovanović et al. 32 who found that certain alternative flours like grape seed and quinoa could improve sensory properties.Similarly, Bakare et al. 33 observed that breadfruit flour had positive effects on sensory qualities.However, at higher substitution levels, there's a noticeable shift in sensory characteristics, www.nature.com/scientificreports/which is also seen in this study at the 30% supplementation level.This aligns with Hussein et al. 18 and Yousef et al. 20 , who noted that while barley and red algae improved nutritional quality, they also led to minor sensory changes.These results suggest a delicate balance between enhancing nutritional value and maintaining sensory acceptability, particularly at higher levels of supplementation of FE or FT.

Freshness of Baladi bread
The effect of storage period (1-3 day) at room temperature on freshness of baladi bread was evaluated as indicated in Table 8 and Fig. 4 indicate that Baladi bread supplemented with FE, particularly at 30%, shows a slower rate of staling compared to control and FT supplemented bread over 72 h.This aligns with studies on bread freshness and staling e.g., Ghoshal et al. 34 found that enzyme supplementation, like xylanase, improves bread freshness and shelf life.El-Sayed 35 highlighted that storage temperature influences bread freshness more than moisture content, pointing to the potential benefits of storing FT-supplemented bread at optimal temperatures.However, Wahab and Elsalam 29 suggested higher protein content, as found in FT-supplemented bread, can improve bread freshness.Collectively, these findings indicate that supplementing Baladi bread with FT, especially at 30%, not only slows down staling but could further benefit from controlled storage conditions and enzyme or protein fortifications to maximize freshness and extend shelf life.

Conclusion
This study confirms that supplementing Baladi bread with FE or FT leads to significant changes in nutritional profile, dough mechanics, color attributes, sensory qualities, and shelf life.Specifically, both Fagopyrum species offer nutritional benefits, such as increased protein and fiber, while imparting varied effects on dough handling and bread quality.FT, especially at 30% concentration, shows promise in slowing down the staling process, thereby potentially extending shelf life.These findings collectively highlight the utility of these alternative flours in enhancing both the nutritional and functional aspects of Baladi bread.

Table 5 .
Chemical composition of Baladi bread supplemented with different levels of FE and FT (on dry weight basis).Where: HWF: Hard wheat flour; FE: Fagopyrum esculentum; FT: Fagopyrum tataricum.Results are presented as means for triplicate analyses ± standard deviation (SD).Means within column with different letters are significantly different (P ≤ 0.05).

Table 6 .
Color attributes for Baladi bread supplemented with different levels of FE and FT.Where: HWF: Hard wheat flour; FE: Fagopyrum esculentum; FT: Fagopyrum tataricum.Results are presented as means for triplicate analyses ± standard deviation (SD).Means within column with different letters are significantly different (P ≤ 0.05).

Table 8 .
Staling of Baladi bread supplemented with different levels of FE and FT.Where: HWF: Hard wheat flour; FE: Fagopyrum esculentum; FT: tataricum.Results are presented as means for triplicate analyses ± standard deviation (SD).Means within column with different letters are significantly different (P ≤ 0.05).